کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1164315 1490988 2014 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Microwave-induced combustion of crude oil for further rare earth elements determination by USN–ICP-MS
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Microwave-induced combustion of crude oil for further rare earth elements determination by USN–ICP-MS
چکیده انگلیسی


• Microwave-induced combustion was applied for light and heavy crude oils digestion.
• It was feasible to determine all the REEs in heavy crude oil by ICP-MS.
• Only diluted acid solutions were used in agreement to green chemistry recommendations.

A procedure for light and heavy crude oils digestion by microwave-induced combustion (MIC) is proposed for the first time for further rare earth elements (REE) determination by inductively coupled plasma mass spectrometry (ICP-MS) equipped with an ultrasonic nebulizer (USN). Samples of crude oil (API density of 10.8–23.5, up to 250 mg) were inserted in polycarbonate capsules and combusted using 20 bar of oxygen and 50 μL of 6 mol L−1 ammonium nitrate as igniter. Nitric acid solutions (1–14.4 mol L−1) were evaluated for analyte absorption and a reflux step was applied after combustion (5 min of microwave irradiation at 1400 W) in order to achieve better analyte recoveries. Accuracy was evaluated using a spiked sample and also by comparison of results obtained by microwave-assisted digestion combined to ultraviolet radiation (MW–UV) and by neutron activation analysis (NAA). Using 3 mol L−1 HNO3, quantitative recoveries (better than 97%) were obtained for all analytes. Blank values were always negligible. Agreement was higher than 96% for La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y by comparison of results with those obtained by MW–UV and by NAA (only for La, Ce, Nd, Sm, and Yb). Residual carbon content in digests using MIC was always below 1%. As an advantage over conventional procedures for crude oil digestion, using MIC, it was possible to use diluted acid as absorbing solution, obtaining better limits of detection and avoiding interferences in REE determination by USN–ICP-MS.

Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Analytica Chimica Acta - Volume 844, 24 September 2014, Pages 8–14
نویسندگان
, , , , , , ,